Nowadays the use of hair brushes is common for hair brushing and soft perms either at home or in hairdressing and beauty salons. An example of commonly used brushes in hairdressing salons are the ones which comprise a hollow and holed tubular body which has a handle for it to be held on one end and a top to close it on its other end. Inside this tubular body are a bunch of fibers arranged helicoidally which come out through the holes of the tubular body. This kind of brush allows making a soft perm and a hairdo while applying heat.
In these brushes the tubular body is made in aluminum coated or not with ceramic which allows the accumulation and transmission of calories provided by an external heat source, generally a hairdryer.
When the tubular body is coated with ceramic it accumulates calories for more time than just aluminum but transmits heat with less speed and effectiveness. Another known inconvenience of this kind of brush is that the hair products applied adhere on the tubular body little by little thus avoiding a smooth and uniform sliding of hair on the tubular body.
Furthermore, another inconvenience of this kind of brush lies in the fibers when emerging through the holes of the tubular body because they do not come out perpendicularly to it due to the fact that normally the holes are circular which cause most of the fibers to lean slightly avoiding the hair sliding smoothly over the brush and making effective contact with the surface of the tubular body, reducing thus the effectiveness of the brush notably, especially during the straightening and soft perm works. In this kind of brush the holes of the tubular body are generally made by means of a die cut on an aluminum plate and during this process little imperfections remain all around the edges of the holes on one of the sides of the aluminum plate.
The presence of these imperfections becomes an important problem during the assembly of the different pieces that compound the brush or during the use of it, because in the case of these imperfections remaining at the internal side of the tube they become a means of retention for the fibers to come out through the tubular body, whereas in the case that the imperfections are on the external side of the tubular body they are so jagged that can damage the hair cuticle.
If it is preferred that the little imperfections are left on one concrete side of the tubular body, the aluminum plates from which the tubular bodies of the brushes will be shaped must be placed in a given position, then the imperfections can be all on the same side, but it slows down the manufacturing process.